Paging systems exist that allow a customer to initiate a page request via a service provider, and have that page message sent to, and acted upon by a specified remote device, such as a numeric pager.
A familiar example would be an implementation of the SkyTel™ paging network which allows users to dial a toll free number, enter a remote pager ID via a telephone menu, and then enter a brief message, typically a telephone number. The SkyTel™ system then communicates the message or phone number to the pager device identified by the remote pager ID via the SkyTel™ pager network.
Paging networks, such as the one-way paging network POCSAG (“Post Office Code Standardization Advisory Group”), PageNet™ (Paging Network, Inc.) and Motorola's “ReFLEX” paging network transmitted paging communications via Frequency Modulated (FM) bands which provided the benefit of having broad coverage, nationwide in many circumstances, but suffered from a narrow Federal Communications Commission (FCC) sanctioned spectrum limiting message size and message volume.
FM based paging networks enjoyed tremendous growth during the late 1980s and early 1990s until the industry peaked during the mid to late 1990s. In the late 1990s, cellular telephone adoption was increasing at a dramatic rate and the FM based paging industry declined quickly.
One active niche market for paging networks is by utility companies to control energy consuming devices within their consumer base for the purpose of smoothing energy demand and improving the efficiency of energy utilization.
In recent years, utility companies have strived to increase their efficiency by reducing the delta between a maximum and minimum amount of energy demand, thus bringing the average energy demand nearer to a predictable baseline of energy demand for the utility company. Unanticipated periods of “peak demand” require utility companies to purchase additional energy capacity from a secondary “spot market” at a much higher cost. Through the use of paging systems, a utility company can instruct multiple remote devices, such as air-conditioning units, to switch off, or otherwise reduce their energy demand, thereby “smoothing” the energy demand, and reducing the utility's overall cost of operation.
Unfortunately, even as utility companies work to develop their capabilities with smoothing energy demand through the remote control of energy consuming appliances, the very mechanism the utility companies use to communicate with the remote devices has been rendered nearly obsolete, and it is unclear for how long FM based paging systems will be available. Furthermore, as the FM based paging system providers lose subscribers and revenue, scales of efficiency are also lost, and an ever-decreasing pool of paying subscribers (e.g., the utility company) must cover the fixed costs associated with the infrastructure, thus increasing the cost to facilitate the energy smoothing programs.
Although the use of digital cellular technology is primarily responsible for the decline of FM based paging networks, it has been heretofore believed that digital cellular networks are incapable of broadcasting a single message to multiple cellular devices simultaneously, due to inherent design characteristics of digital cellular networks. For example, Code Division Multiple Access (CDMA) digital cellular networks identify and communicate with remote devices through the use of Device Identifiers (e.g., a Mobile Identification Number (MIN), a unique 10-digit number, or an International Mobile Subscriber Identifier (IMSI), a unique 15-digit number), that identify a particular remote device operating within a digital cellular communication network. As an additional example, Global System for Mobile communications (GSM) digital cellular networks also identify and communicate with remote devices through the use of an IMSI. Each remote device only “listens for” or reacts to messages and information that are directed toward its particular Device Identifier.
Because each remote device on a digital cellular network is associated with a single unique Device Identifier, a utility company wishing to contact a group of remote devices to send data, or trigger an event, faces two critical problems. First, initiating individual messages to each individual remote device via its unique Device Identifier is cost prohibitive as the utility company must pay a third-party cellular provider for each individual message sent. This would be akin to making thousands of short individual phone calls or sending thousands of text messages or initiating thousands of separate cellular Internet Protocol (IP) data sessions, each time the utility company wishes to send data or trigger a remote event in multiple remote devices. The third-party cellular provider requires compensation for the use of its network infrastructure. Generating potentially thousands of calls or messages or data sessions in a short period of time would induce a massive amount of traffic, and thus, is very expensive compared with sending a single page to multiple remote devices simultaneously over the FM based paging networks.
Secondly, because the messages must be individually addressed and transmitted to each individual remote communication device via its unique Device Identifier, the length of time required to communicate instructions to the remote devices increases dramatically as the volume of outgoing messages increases. For a utility company to benefit from small decreases in energy consumption among individual energy consuming appliances, the utility company must orchestrate a corresponding energy decrease among thousands and potentially tens of thousands of such appliances within the utility company's service area. Any delay in communicating the required instructions could potentially obviate much of the potential benefit of instructing a large number of energy consuming appliances to scale back during a period of peak energy demand. This problem is exacerbated if the peak demand is unanticipated and the utility company is attempting to quickly reduce overall system demand.